Hi Nick - can't believe you haven't gotten a single reply on this. Probably because the same question has been asked in other places. If you see my post:
you can see that we have been dealing with this issue for quite sometime. No resolution. Don't know if its our firewall preventing 'outStatistics' from being displayed or not. But no, Hub seems to index attributes at random. It's problematic for us because all of our open data goes to our agol org - open data groups via collaboration. When anyone tries to chart a variable they get an error, which throws an error in our portal's hosted site logs.
Hi David - I forgot I posted this question.
I've reviewed your post and can confirm my Open Data site has the same problem:
Initially, my question was with regards to customizing the attributes section.
The error occurs for datasets from both ArcGIS Server & AGOL hosted.
This is a bug. I suspect it has already been reported?
Hi Nick - No, I don't think anything has been reported.
At the moment, for us anyway, the errors have decreased but not disappeared entirely. It's hard to say if our Open Data site is the only culprit, but it's certainly one of them. As far as what attributes are picked for mapping and charting, I have no idea how they are doing that.
So I can't exactly speak to what's causing the error posted in Nick's screenshot -- usually when those errors pop up on fields that *can* be charted, it's due to the query being made to the underlying service returning an error or invalid response. The reason as to why exactly that happens can vary (it could be service or even data specific) and if you'd like to troubleshoot those kinds of issues, I'd definitely suggest logging a case with Support to look into it more.
With that being said, I can hopefully shed some light on why certain fields can or can't be charted. Both the Chart and Map visualizations are limited to fields that have 20 or fewer unique values, so any field that has more unique values than that will not have the chart or map visualization (like your ObjectID fields). This is mentioned in a brief note on the documentation pages for these two visualizations:
I hope this helps clear things up!
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